Description
Calibrate skin-image length and compare scale values.
Skin-image research can record scale, annotation geometry, visibility and timing. Pixel counts, mask components and supplied metadata are technical summaries rather than disease findings or proof an image is suitable for diagnosis.
Calibrate skin-image length and compare scale values.
When to use this tool
Use Skin Image Scale Reference Ratio when checking a supplied dermatology research image or annotation record.
How to use the tool and how it works
- Enter imagePixels, referencePixels, suppliedReferenceLength, secondScale. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read physicalLength, scaleRatio. Use the output convention below.
Calibrate skin-image length and compare scale values. Require nonnegative imagePixels and positive referencePixels, suppliedReferenceLength and secondScale; physicalLength = imagePixels*referenceLength/referencePixels, scaleRatio = (referenceLength/referencePixels)/secondScale.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| imagePixels | Image Pixels | Required. Finite number; minimum 0. |
| referencePixels | Reference Pixels | Required. Finite number; strictly above 0. |
| suppliedReferenceLength | Physical reference length; output uses this same length unit. | Required. Finite number; strictly above 0. |
| secondScale | Second Scale | Required. Finite number; strictly above 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| physicalLength | Physical Length | Required. Finite number. |
| scaleRatio | Scale Ratio | Required. Finite number. |
{
"input": {
"imagePixels": 40,
"referencePixels": 20,
"suppliedReferenceLength": 5,
"secondScale": 0.5
},
"output": {
"physicalLength": 10,
"scaleRatio": 0.5
}
}Limitations and assumptions
- secondScale is physical length per pixel; no lesion diagnosis or image calibration validity is established.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Use calibrated imaging and professional clinical assessment for any health interpretation; validate annotation and measurement methods separately.
References
Similar or alternative tools
- Skin Image Ruler Plane Offset
Apply a supplied ruler-plane correction to image length.
- Skin Image Region Resolution Gap
Compare image-region pixel dimensions with supplied targets.